GPS RTK robot mower

[Miles Teg]

Hello Forum,
I’m opening a subject here to follow my new personal project.
Name: Yet another GPS robot mower.

Don’t know if there is already equivalent project here. I made a little research on the forum and found nothing associated.

Little story: Since 2013 I was making EE design on audio, UI prototype for microwave oven, kitchen robot.
End 2019, last electronic project on a nice domotic gateway with LCD screen (google home like)/
2020 I switch 100% to environmental project management for my big retail company. Carbon footprint, Life Cycle Assessment, ecodesign. I was excited and involved in this.

End 2021, burn out, depression. 

Nearly one year later and 9 months off I’m maybe 80% back. I leave this company and I’m willing to get back to EE.
I still have free time maybe until this end 2022. And to test myself and gest used again to electronic design, thinking, EDA, programming… 

Got already a functioning Robot mower (Worx) at home. Doing it’s job, but I’m a little bit frustrated by its logic and how it could remain stuck sometimes (too often…)

I’ve discovered the openmower project through this video:
Found that great, will help to adjust easily the lawn perimeter without moving wires, and let the robot get access by itself to the 3 other small areas around my house (200+80+30m²).
So good project to get brain at work again and could have nice finality at home.

Here is the old robot mower I found for 140€, a biffy ~40kg, 3 blades, 24V lead batteries robot. RL2000

T-72 like


Aside my not so small Honda mower


Before cleaning



Would be great to share with you my progress and questions.
I’m confident on the HW, but still have lot of questions on the SW choice. Go on Ardumower or Openmower “frameworks”? Or adapt mine with help of a SW engineer friend?

Hope this project will create some interest here. I got back in few minutes presenting first block diagrams, component search…

[Miles Teg]

Here is my actual block diagram, with listed inputs, actuators present on the mower



Driving motors should be ok with the use of 3 DRV8432, on 2 separated boards.

On GPS side, before maybe integrating the GPS module directly on main board I will use the Ardusimple F9R module
On Xbee connector I need to find an ESP32 like thing to provide correction GPS RTK from internet to the GPS module. Wifi module should be use also to provide orders and data to main CPU/MCU

Need to experiment battery, BMS and design power supplies around a 7S3P 24V 10Ah LiIon battery.
DC/DC covnerter for battery charge would be a on shelf module.
-> Need to find a good brand for this Pack + BMS

And finally get study on OpenMower and Ardumower to know best SW solution to start designing the CPU or MCU solution. Maybe get our own adapter Ardumower on a ST32F4. Will need to adapt or design the base control SW.